An insulating underlay element for arranging between a subfloor and floor coverings laid thereon. The underlay element comprises a push-in connection on at least two sides of the insulating underlay element for connecting the insulating underlay elements to form an extensive insulating underlay in a gap-free and extensive manner, wherein an adhesive strip is arranged on the underside of the insulating underlay element in the region of the push-in connection, such that the adhesive surface is facing upward in the receptacles of the push-in connections and is in contact with the undersides of the pushed-in protrusions. The adhesive strip comprises a backing material coated with a release adhesive, and the insulating underlay elements being coated on their underside with a permanent adhesive in the region of the arrangement of the adhesive strips to establish a permanent adhesive connection between the adhesive strips and the underside of the insulating underlay element.